Transfer layer for absorbent article

ABSTRACT

A film particularly suited for use as a transfer layer in an absorbent article has a plurality of capillaries and a plurality of drains, said capillaries comprising side walls depending from a female side of the film and terminating in an aperture on a male side of the film; said drains comprising side walls that depending from the female side of the film and terminating in an aperture on the male side of the film, wherein the drains are disposed at an obtuse angle relative to a base plane of the film.

BACKGROUND OF THE DISCLOSURE

The disclosure relates to formed films, more specificallythree-dimensional formed films for use as transfer layers in absorbentarticles.

Absorbent articles are articles that are generally used once or alimited number of times for the temporary collection and immobilizationof bodily fluids. Such articles include diapers, adult incontinentproducts, feminine hygiene products, bandages and similar articles. Ingeneral, these articles have a topsheet, which is positioned adjacentthe skin of the user, a backsheet, which is opposite the topsheet andmay, in use, be positioned adjacent to the clothes of the wearer, and anabsorbent core positioned between the topsheet and the backsheet. Inmost instances, the topsheet is pervious to the bodily fluids and thebacksheet is impervious to such fluids, thus protecting the clothing ofthe wearer from leaks. The absorbent core is designed to collect andhold the bodily fluids until the article can be disposed of and replacedwith a fresh article.

Transfer layers, which are also known in the art as acquisitiondistribution layers or “ADC”, have been used in absorbent articles. Bothnonwoven webs and three-dimensional formed films have found use astransfer layers in the past. A transfer layer is typically positionedbetween the topsheet and the absorbent core and generally improves theefficiency of the article to absorb and retain fluids. For example,transfer layers have been used to provide void volume, which serves as atemporary reservoir to collect and hold fluids until the fluids can beabsorbed by the core. In addition, transfer layers have been employed topromote lateral flow of fluids in a direction generally parallel to theplane of the transfer layer, thereby permitting more of the core to beused to absorb fluids. See, for example. U.S. Pat. No. 4,324,247.

There is a continuing need for transfer layers that more effectivelypromote distribution of fluids over the absorbent core, provide morecomfort for the wearer, reduce surface wetness in the topsheet, andprevent or reduce rewet.

SUMMARY OF THE DISCLOSURE

In one embodiment, the disclosure provides a formed film for use as atransfer layer, the film having a plurality of three-dimensionalcapillaries and plurality of three-dimensional drains, wherein thedrains are disposed at an obtuse angle relative to the base plane of thefilm.

In another embodiment, the disclosure provides a formed film for use asa transfer layer, the film having a plurality of three-dimensionalcapillaries and plurality of three-dimensional drains, wherein thedrains are disposed at an obtuse angle relative to the base plane of thefilm and the capillaries are disposed at an angle approximately normalto the base plane of the film.

In another embodiment, the disclosure provides a formed film for use asa transfer layer, the film having a plurality of three-dimensionalcapillaries and plurality of three-dimensional drains, wherein thedrains are disposed at an obtuse angle relative to the base plane of thefilm and wherein the drains and the capillaries terminate in a commonplane.

These and other embodiments will be apparent from a reading of thedetailed description, with reference to the drawings, and the appendedclaims.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a cross-sectional view of an absorbent article having atransfer layer in accordance with an embodiment of the disclosure.

FIG. 2 is a graph of grams of liquid versus time.

FIG. 3 is a graph of grams of liquid versus time

DETAILED DESCRIPTION OF THE EMBODIMENTS

Absorbent articles generally comprise a topsheet, an absorbent core, anda backsheet. The topsheet is on the body facing side of the absorbentarticle and typically comprises a liquid pervious material that allowsliquid from an insult to transfer from the body-facing surface of theabsorbent article to the absorbent core. The term “insult” generallyrefers to an amount of a liquid or the act of adding a liquid on atopsheet of an absorbent article. An insult may occur during product useand during finished product testing. Consequently, “multiple insults”occur when the same absorbent article is insulted more than once. Thetopsheet is typically in close proximity or even direct contact with thewearer's skin during use and is typically made of a son material such asa nonwoven material, an apertured film, or a combination of thesematerials made into a unitary composite. The topsheet is typicallydesigned to retain a comfortable, dry feel to the wearer even after aninsult.

The backsheet is positioned on the garment facing side or outsidesurface of the absorbent article. A backsheet may be a liquid imperviousfilm that does not allow liquid to transfer from within the absorbentarticle to the exterior surface of the absorbent article or to thegarment of the wearer. A breathable backsheet is impervious to liquid,yet allows water vapor to pass out of the absorbent article. This lowersthe humidity felt by the wearer and thereby increases the comfort to thewearer.

The absorbent core absorbs the insult and retains the liquid while theabsorbent article is in use. The absorbent core should adequately absorban insult or multiple insults and substantially retain the insult untilthe absorbent article is removed and discarded. The storage capacity ofthe absorbent core and the efficiency of distribution of an insultacross the absorbent core determine the amount of liquid that may beheld in the absorbent article. The absorbent material in an absorbentcore may comprise any liquid absorbent material such as, but not limitedto, cellulose materials including fibers, cellular sponge or foammaterials, super absorbent materials, such as superabsorbent polymers,hydrocolloidal materials, gel materials and combinations thereof. It iswithin the contemplated scope of the present disclosure that one or moreof these types of absorbent materials are useful in embodiments. Inparticular, in certain embodiments, the absorbent material may comprisea mixture of absorbent granular materials and finely chopped cellulosefibers.

Particularly useful absorbent materials are high absorbency gel-typematerials which are generally capable of absorbing about 10 to about 50times their weight in fluid. As is generally known in the art, the rateat which the core absorbs liquids is inversely proportional to theability of the core to hold the liquids absorbed. Thus, thesuperabsorbent materials used in cores are very good at holding liquids,but are relatively slow at liquid uptake. The delay in liquid uptakeresults in more unabsorbed or free fluid in the article, and thusdecreases the rewet performance of the article. Because use of thesematerials has other benefits, such as reduced bulk of the core, theslower uptake is generally outweighed by the other advantages.

In accordance with the embodiments, the transfer layers are locatedbetween the topsheet and the absorbent core or between the backsheet andthe absorbent core. Most preferably, the transfer layers are locatedbetween the topsheet and the core.

Transfer layers may function to control rewet, a phenomenon wherebyunabsorbed or “free” fluid within the article is present on or withinthe user-contacting surface of the article. Rewet is comprised of asurface wetness component and a back wetting component. Surface wetnessrefers to liquids that remain on the surface of the topsheet or withinthe porosity of the topsheet after an insult. Back wetting refers tofluids that have once passed through the topsheet but transfer back tothe topsheet surface. Back wetting is generally more pronounced when thearticle is under load or compression, whereby fluids are forced backthrough the topsheet. The compression can occur, for example, when aninfant urinates in the diaper and then sits. Liquids present at orwithin the surface of the topsheet, by whatever mechanism, create anunpleasant, damp feeling to the user of the article. Thus, minimizing oreliminating rewet is important for consumer acceptance. Transfer layerscan control rewet by providing a physical restriction to back wetting.In particular, a film material acts as a physical barrier because thefilm itself is liquid impermeable and the apertures are generally shapedto restrict the flow of liquids away from the absorbent core. Nonwoventransfer layers, however, provide a temporary reservoir and collectfluids before they reach the topsheet surface. In certain situations,transfer layers can also reduce surface wetness on the topsheet byfacilitating transfer of stationary fluids that would otherwise tend toremain on the topsheet.

In standard industry tests, such as EDANA ERT 151.2-99 or EDANA ERT151.3-02, rewet is measured by subjecting the article to a measuredinsult of fluid, waiting 10 minutes, and then applying blotter paper anda weight to the topsheet and measuring the amount of liquid acquired bythe blotter paper. The reason for the 10 minute delay is to allow theabsorbent core time to acquire the liquid. As a practical matter,however, the user of the article does not want the wet sensation to lastfor 10 minutes as it can be a very unpleasant feeling. Thus, from aconsumer perspective, near instantaneous dryness following an insult isrequired.

An insult may be considered to include a combination of both dynamic andstationary fluid. The dynamic fluid flows through the topsheet andtransfer layer at the time of insult while the stationary fluid may beretained within a porosity of the topsheet and/or transfer layer. Toremove the stationary fluid, a transfer layer must be capable ofsustaining z-direction wicking or capillary action. When the transferlayer is a three-dimensional formed film, z-direction wicking orcapillary action is accomplished by providing at least a portion of theapertures that are sufficiently small in diameter to achieve capillarityor capillary action.

As mentioned, both films and nonwoven fibrous webs have been used asboth topsheets and transfer layers. Nonwoven webs have internal voidspace between the fibers that can attract and hold liquids. Thus,nonwoven webs provide a temporary or “buffer” reservoir for fluids. Whenan insult occurs, fluids accumulate in the pore spaces of a nonwoven,whether it is used as a topsheet or a transfer layer, until the fluidshave an opportunity to drain out and/or be absorbed by the core. Thebuffer function of the nonwoven works in both directions. Specifically,when an insult occurs, the nonwoven acts as a buffer to hold fluidsuntil they can drain out and be absorbed by the core. Once the fluidshave drained out, the nonwoven can act as a buffer to accumulate fluidsbefore they reach the topsheet surface. The amount of fluids that drainout, and the time to do so, as well as the buffer capacity of thenonwoven are dependent upon the size of the pores between the fibers ofthe nonwoven web, the relative hydrophilicity/hydrophobicity of thenonwoven, the fiber density, and other factors. Immediately after aninsult, the void capacity of the nonwoven is essentially full and thecore has not had sufficient time to absorb the insult. Thus, there is nocapacity for the nonwoven to act as a buffer to fluids transferring backto the topsheet surface. The portion of the insult that passes throughthe nonwoven web but is not yet absorbed, as well as the portion that istemporarily retained within the pores of the web can contribute torewet.

With a formed film, however, except for a small amount of fluid thatmight remain in the land areas between the apertures, the insult isnearly instantaneously passed through the film and stored in the voidspace on the underside of the film. If a load is applied at that time,the film acts as a physical harrier to rewet and it is only the fluidsthat find their way back through the apertures that contribute to rewet.Because the apertures in formed films are typically tapered to have anarrower opening on one side (i.e.; the “male” side) verses the oppositeor “female” side, the films exhibit a preferential liquid flow towardsthe core and are practically liquid impervious in the oppositedirection. As a result, formed films can provide near instantaneousdryness in an absorbent article whereas nonwoven webs do not. Indeed,testing has shown that films are superior to nonwoven webs in rewetperformance, particularly when tested immediately after an insult. Withthe passage of time following an insult, the nonwoven has an opportunityto drain out and can again function as a buffer to fluid transfer fromthe core area to the topsheet surface. Thus, the difference in rewetperformance when using films as opposed to nonwoven webs is lesssignificant as time after insult increases.

Reported in Table 1 are the grams of liquid obtained using a standardrewet test procedure as a function of time after insult.

TABLE 1 Time (minutes after insult) sample 0 2 4 6 8 10 Size 4 diaperwith 16.32 0.51 0.50 0.30 0.24 0.32 nonwoven transfer layer (firstinsult) Size 4 diaper with 1.37 0.29 0.34 0.32 0.22 0.21 film transferlayer (first insult) Size 4 diaper with 48.65 32.71 22.31 17.68 20.0512.97 nonwoven transfer layer (third insult) Size 4 diaper with 24.5914.25 9.17 5.43 5.34 4.77 film transfer layer (third insult)

The data from Table 1 is plotted and illustrated in FIGS. 2 and 3 asgraphs of grams of fluid versus time. More specifically. FIG. 2 depictsresults obtained when measuring rewet after acquisition of a firstinsult. Curve 100 represents an article using a film and curve 200represents an article using a nonwoven. As seen in FIG. 2, the use of afilm results in significantly less rewet immediately after insult ascompared to using a nonwoven. In time, the difference between films andnonwovens is negligible, but films clearly provide a more immediatesensation of dryness. These data indicate that immediately after a firstinsult, baby diapers using nonwoven transfer layers can produce 6-16grams more liquid in the rewet test as compared to identical articlesusing formed films.

With reference to FIG. 3, illustrated therein is a curve of grams liquidversus time of a rewet test after a third insult. The data show thatarticles using formed films as transfer layers (curve 300) showedsignificantly less surface liquids as compared to articles usingnonwovens as transfer layers (curve 400). The difference is similar tothat seen in the conditions for FIG. 2; i.e., the articles using formedfilms had 6-26 grams less liquid versus articles using nonwoven webs.

Transfer layers in accordance with the embodiments are films. As usedherein, a “film” refers to a thin polymer sheet or web. A film may beproduced, for example, by extruding a molten thermoplastic polymer in acast or blown extrusion process and may be further processed betweenrollers and cooled to form the web. Films can be monolayer films orcoextruded films, for example.

The term “polymer” includes homopolymers, copolymers, such as, forexample, block, graft, random and alternating copolymers, terpolymers,etc., and blends and modifications thereof. Furthermore, unlessotherwise specifically limited, the term “polymer” is meant to includeall possible geometrical configurations of the material, such asisotactic, syndiotactic and atactic or random symmetries.

The transfer layers may be dimensionally described as having a machinedirection, a cross direction, and a z-direction. The machine directionis defined by the direction in which the film passes through themanufacturing process. Typically, films are produced as long sheets orwebs having a much greater length than width. In such a case, themachine direction is usually the length (also referred to as thex-direction) of the sheet. Perpendicular to the machine direction is thecross direction or transverse direction (also referred to as they-direction or width) of the sheet. The thickness of the film (sometimesalso referred in certain embodiments as loft or caliper of the film) ismeasured in the z-direction.

Three-dimensional formed films include a base plane forming the nominalthickness of the film, and include structures originating on the surfaceof the film and protruding outwardly in the z-direction. The dimensionsof these structures provide the film with a z-direction dimension thatis greater than the nominal thickness of the film. They also provide thefilm with a secondary plane defined by the surface structures and spacedfrom the base plane of the film in the z-direction. Thethree-dimensional features of the three-dimensional formed films may beproduced in an embossing process, a hydroforming process, or a vacuumforming process, for example. All such processes are well known in theart.

A “multiplanar film” is a three-dimensional formed film that hasadditional surface structures that originate from both the base planeand the secondary plane of the film. For example, a formed film having amultiplanar structure may comprise a plurality of plateaus that are onthe surface of the film, the plateaus defining at least one additionalplane of the film above or below the base surface. In certainembodiments of the multiplanar three-dimensional formed film,protuberances may be formed on any or all of the available planes.

A three-dimensional apertured formed film is simply a formed film thathas openings or apertures in the three-dimensional structures. The size,spacing and other properties of the apertured three-dimensionalstructures are based upon the particular apparatus used to create thethree-dimensional apertured formed film. For example, in a vacuumforming process, a hydroforming process, and some mechanical processes,the size, shape and spacing of the apertures is determined by theforming structure that supports the film while the is subjected tovacuum pressure, pressurized water streams, or mechanical perforationdevices such as pins. See, for example U.S. Pat. No. 4,456,570 and U.S.Pat. No. 3,929,135.

For apertured formed films, the z-direction dimension of thethree-dimensional structure is a function of the diameter of thethree-dimensional structure, which, in turn, is a function of thediameter of the apertures in the forming structure or the diameter ofthe perforating pin. For example, smaller diameter structures typicallyhave a smaller z-direction dimension as compared to larger diameterstructures. Other factors also contribute to the z-direction height ofthe three-dimensional features such as film composition, basis weight ofthe film, temperature of the film while being apertured, as well asother process conditions and apparatus-related factors.

For example, three-dimensional formed films may comprise at least onepolymer selected from polyolefins (e.g., C₂-C₁₀ olefins such aspolyethylene, polypropylene, etc.); polyesters; plastomers; polyamides(e.g., nylon); polystyrenes; polyurethanes; vinyl polymers; acrylicand/or methacrylic polymers; elastomers (e.g., styrene block copolymerelastomers); polymers from natural renewable sources; biodegradablepolymers; and mixtures or blends thereof. Preferably, the polymer is athermoplastic polymer.

Additionally, any of a variety of additives may be added to the polymersand may provide certain desired characteristics, including, but notlimited to, roughness, reduction of anti-static charge build-up,abrasion resistance, printability, writeability, opacity,hydrophilicity, hydrophobicity, processibility, UV stabilization, color,etc. Such additives are well known in the industry and include, forexample, calcium carbonate (abrasion resistance), titanium dioxide(color and opacity) and silicon dioxide (roughness), surfactants(hydrophilicity/hydrophobicity), process aids (processibility), etc.

Referring to the embodiment of FIG. 1, absorbent article 10 comprises atopsheet 12, a core 14, a backsheet 16 and a transfer layer 15positioned between the core 14 and topsheet 12. The article 10 has abody facing surface 13 which, in use, would be placed adjacent to orotherwise in close proximity with the skin of the user. The article 10also has a garment facing surface 17 which is opposite the body facingsurface 13. The garment facing surface 17, in use, would be in proximityto the garment of the user or to the environment if the absorbentarticle is a bandage, wound dressing, surgical drape or the like.

Topsheet 12 comprises a fluid pervious material to allow fluids to enterthe absorbent article 10. Topsheet 12 is generally an apertured film,such as an apertured formed film, a nonwoven web, or composites. In theembodiments illustrated, the topsheet 12 comprises a nonwoven web.Backsheet 16 is generally fluid impervious to prevent leakage of fluidsfrom the absorbent article. Films, nonwoven webs and composites aretypically used for the backsheet. In the embodiments shown, thebacksheet 16 comprises a liquid impervious blown or cast film. Theabsorbent core 14 is between the topsheet 12 and the backsheet 16 andcomprises materials that can absorb and retain fluids that pass throughthe topsheet until the article is discarded.

As seen in FIG. 1, the transfer layer 15 comprises a three-dimensionalformed film having a plurality of three-dimensional capillaries 18 andplurality of three-dimensional drains 25. The capillaries 18 compriseprotuberances comprising cone-shaped structures with side walls 20 thatoriginate on the female side 21 of the film 15 and extend in az-direction (indicated by arrow “Z” in FIG. 1) from the female side 21of the film 15. The capillaries 18 terminate in an aperture 22 on themale side 23 of the film 15.

Capillaries 18 are sized to provide fluid transport via capillary actionand promote removal of a stationary portion of the insult retained onthe topsheet surface or within the porosity of the topsheet by providingsustained z-direction wicking. The z-direction wicking improves rewetperformance by reducing either the surface wetness component or the backwetting component, or both. This z-direction wicking is accomplished byproviding the capillaries 18 with a diameter that is sufficiently smallto achieve capillarity.

For sustained capillary action to occur, it is necessary to provide somemechanism to remove fluids from the exit side (i.e., at aperture 22) ofthe capillary 18. One convenient mechanism in absorbent articles is toplace the exit side of the capillary in intimate contact with theabsorbent core. This has been difficult to execute in prior art transferlayers, however, particularly in those transfer layers also containinglarger diameter protuberances. Specifically, the larger diameterprotuberances, which are necessary to provide for rapid acquisition ofthe dynamic portion of an insult, would generally be of greaterdimension in the z-direction than the smaller diameter capillaries.Accordingly, for the capillaries to make intimate contact with the core,the larger protuberances would need to be crushed for achieving intimatecontact. This is, of course, contraindicated because it defeats thepurpose of the larger protuberances. Accordingly, in prior art films,the capillaries would be suspended above the absorbent core in the void(i.e., empty) space and thus fail to provide for sustainable removal ofliquid.

The transfer layer 15 further includes a plurality of drains 25. Thedrains 25 are three-dimensional structures having side walls 26 thatoriginate on the female side 21 of the film 15 and extend in thez-direction as seen in FIG. 1. The drains 25 terminate in an aperture 27on the male side 22 of the film 15. The drains 25 are of a largerdiameter than the capillaries 18 and permit the rapid transfer of fluidsfrom the female side 21 of the film 15 to the male side 23 of the film.

As seen in FIG. 1, the drains 25 are oriented to form an angle 29relative to the base plane 28 of the film 15. The angle 29 is greaterthan 90 degrees relative to the base plane 28, such that drains 25 forman obtuse angle relative to the base plane 28 of the film 15. The angle29 is not particularly important, and may generally be in the range of100-175° relative to the base plane 28. Films having such angularprotrusions are known in the art and disclosed, for example, in EP1040801; WO 1997/003818; and WO 2000/016726. each of which isincorporated herein by reference.

Because drains 25 are disposed at an obtuse angle relative to the baseplane 28 of the film 15, the drains do not extend in the z-direction asmuch as they would if they were oriented normal to the base plane 28.Accordingly, the angular orientation of the drains 25 permits theapertures 22 of the capillaries 18 to remain in intimate contact withthe core 14, which provides the mechanism needed to maintain sustainedcapillary action in wicking fluids away from topsheet 12. Stateddifferently, as seen in FIG. 1, the drains 25 and capillaries 18 allterminate in a common plane 30 that is generally parallel to and spacedfrom the base plane 28 of the film 15.

The angled orientation of the drains 25 also serves to at leastpartially occlude the sight line through the film 15 to the core layer14. Accordingly, the films 15 also serve a masking function in at leastpartially hiding the core 14.

The drains 25 may be any desired size that permits rapid passage of thefluids. For example, the drains 25 of certain embodiments may have anaverage cross sectional area greater than 0.2 mm² and an averagehydraulic diameter between 0.55 mm and 1.2 mm. The capillaries 18, bycontrast, have an average diameter between 50 microns and 400 microns asmeasured on the female side 21. The ratio of the hydraulic radius of thedrains 25 to the capillaries 18 will generally exceed 3:1 and in mostcases will be 4 or 5:1 or higher. Ratios of 10:1 or more are alsocommon.

In the embodiment shown in FIG. 1, the capillaries 18 and drains 25 aregenerally conical. However, is it to be understood that the shape ofthese structures is not particularly significant. In particular, thecapillaries and drains may have a shape that is circular, oval,triangular, square, pentagonal, hexagonal, or any other desired shape.

The transfer layer may be oriented in the absorbent article with eitherthe male side or female side facing the absorbent core. In manyapplications, the male side of the transfer layer will face theabsorbent core, but in some applications it may be desirable for thefemale side to face the core.

Any design or pattern may be formed to produce embodiments of thetransfer layer. Any ratio of drains to capillary-sized protuberances maybe used. Depending on the applications, more or fewer capillary-sizedstructures may be desired as compared to the embodiments illustrated inFIG. 1.

It is to be understood that although this disclosure describes severalembodiments, various modifications apparent to those skilled in the artmay be made without departing from the invention as described in thespecification and claims herein.

1.-15. (canceled)
 16. A formed film having a female side and a maleside, the formed film comprising: a plurality of capillaries extendingfrom the female side of the formed film and terminating in one or moreapertures on the male side of the formed film, wherein each of theplurality of capillaries comprise sidewalls; and a plurality of drainsextending from the female side of the formed film and terminating in oneor more apertures on the male side of the formed film, wherein each ofthe plurality of drains comprise sidewalls slanted at an angle relativeto a base plane of the formed film, and wherein the angle of the slantof the sidewalls of the plurality of drains is different than an angleof the sidewalls of the plurality of capillaries.
 17. The formed film ofclaim 16, wherein the angle comprises an obtuse angle.
 18. The formedfilm of claim 17, wherein the obtuse angle is about 100-175° relative tothe base plane of the formed film.
 19. The formed film of claim 16,wherein the plurality of drains have an average cross sectional areagreater than 0.2 mm² and an average hydraulic diameter between 0.55 mmand 1.2 mm.
 20. The formed film of claim 16, wherein the plurality ofcapillaries have an average diameter between 50 microns and 400 micronsas measured on the female side of the film.
 21. The formed film of claim16, wherein the ratio of the hydraulic radius of the plurality of drainsto the plurality of capillaries is greater than 3:1.
 22. The formed filmof claim 16, wherein at least one sidewall of a drain of the pluralityof drains is parallel to at least another sidewall of another drain ofthe plurality of drains and not parallel to the sidewalls of theplurality of capillaries.
 23. A formed film having a female side and amale side, the formed film comprising: a plurality of capillariesextending from the female side of the formed film and terminating in oneor more apertures on the male side of the formed film, the plurality ofcapillaries comprising sidewalls; and a plurality of drains extendingfrom the female side of the formed film and terminating in one or moreapertures on the male side of the formed film, the plurality of drainscomprising sidewalls, wherein at least one sidewall of a drain of theplurality of drains is parallel to at least another sidewall of anotherdrain of the plurality of drains and not parallel to the sidewalls ofthe plurality of capillaries.
 24. The formed film of claim 23, whereinthe plurality of drains have an average cross sectional area greaterthan 0.2 mm² and an average hydraulic diameter between 0.55 mm and 1.2mm.
 25. The formed film of claim 23, wherein the plurality ofcapillaries have an average diameter between 50 microns and 400 micronsas measured on the female side of the film.
 26. The formed film of claim23, wherein the ratio of the hydraulic radius of the plurality of drainsto the plurality of capillaries is greater than 3:1.
 27. The formed filmof claim 23, wherein the sidewalls of the plurality of drains areslanted at an angle relative to a base plane of the formed film, andwherein the angle of the slant of the sidewalls of the plurality ofdrains is different than an angle of the sidewalls of the plurality ofcapillaries.
 28. The formed film of claim 27, wherein the anglecomprises an obtuse angle.
 29. The formed film of claim 28, wherein theobtuse angle is about 100-175° relative to the base plane of the formedfilm.
 30. A formed film having a female side and a male side, the formedfilm comprising: a plurality of capillaries extending from the femaleside of the formed film and terminating in one or more apertures on themale side of the formed film, wherein each of the plurality ofcapillaries comprise sidewalls; and a plurality of drains extending fromthe female side of the formed film and terminating in one or moreapertures on the male side of the formed film, wherein each of theplurality of drains comprise sidewalls slanted at an angle relative to abase plane of the formed film, wherein the angle of the slant of thesidewalls of the plurality of drains is different than an angle of thesidewalls of the plurality of capillaries, and wherein at least onesidewall of a drain of the plurality of drains is parallel to at leastanother sidewall of another drain of the plurality of drains and notparallel to the sidewalls of the plurality of capillaries.
 31. Theformed film of claim 30, wherein the angle comprises an obtuse angle.32. The formed film of claim 31, wherein the obtuse angle is about100-175° relative to the base plane of the formed film.
 33. The formedfilm of claim 30, wherein the plurality of drains have an average crosssectional area greater than 0.2 mm² and an average hydraulic diameterbetween 0.55 mm and 1.2 mm.
 34. The formed film of claim 30, wherein theplurality of capillaries have an average diameter between 50 microns and400 microns as measured on the female side of the film.
 35. The formedfilm of claim 30, wherein the ratio of the hydraulic radius of theplurality of drains to the plurality of capillaries is greater than 3:1.